The origin of the sensory deprivation tank
Floatation therapy is based on a scientific approach to deep relaxation called Restricted Environmental Stimulation Technique or R.E.S.T. for short. The idea was developed in the mid 1950's at the National Institute of Mental Health by a neuroscientist named Dr. John C. Lilly. Lilly was a pioneer in his field. Some of his accomplishments included being the first person to map the pain and pleasure pathways in the brain, as well as creating an entirely new branch of science aimed at interspecies communication. It was clear that Lilly had an infatuation with the power of the human brain. It was that drive that led to one of the greatest discoveries of the century.
The isolation chamber was created through a question that Lilly was determined to answer. What keeps the brain going? The argument was, that the brain was biological and completely internal, meaning that it made no difference whether outside interference was present as it would operate normally either way. Others claimed that if all external stimulation was removed, then the brain would completely shut down. Lilly began constructing a chamber that would isolate all stimulation in order to find an answer to this question. A mask was worn to isolate sight and sound. The water inside the tank was heated as well, isolating the sense of touch (feeling). What transpired next was truly astonishing.